In North America, there is a significant cottage industry based around the preparation of fleeces for hand spinning. Animals are shorn in the spring to create fleeces. The fleeces are often washed. A picking device will pick apart the (possibly washed) fleece to prepare it for a carding machine. The carding machine creates roves of wool that are aligned to make hand spinning easier. The spun wools and fleeces are then used in a variety of textile arts such as weaving, knitting, crochet, felting and macramé.
Why pick apart the fleece? Most wool bearing animals spend most, if not all, of their time outdoors in pastures or pens. Their coats become deeply impregnated with dirt, sticks, brambles, straw and other debris. Washing the shorn coats removes some of the dirt, but the hair or wool tends to become even more clumped up. Picking it apart is extremely useful because until that is done, it is often very difficult and/or impossible to run the fleece through a carding machine, which is the next step.